title: Evaluation of simulated external root resorptions with digital radiography and digital subtraction radiography.
abstract: BACKGROUND
  Root resorption can cause damage in orthodontic patients. Digital subtraction radiography (DSR) is a useful resource for the detection of mineral losses. The purpose of this study was to compare the efficacy of digital radiography (DR) and DSR in detecting simulated external root resorption. Examiner agreement between the 2 techniques was also evaluated.
  
  
  METHODS
  Root resorptions of various sizes were simulated on the apical and lingual aspects of 49 teeth from 9 dry human mandibles. The teeth were radiographed in standardized conditions. The radiographs were registered with Regeemy Image Registration and Mosaicking (version 0.2.43-RCB, DPI-INPE, São José dos Campos, São Paulo, Brazil) and subtracted with Image Tool (University of Texas Health Science Center at San Antonio). The subtracted images and the digital radiographs were evaluated by 3 oral radiologists.
  
  
  RESULTS
  No statistically significant differences were found for the methods in the detection of apical root resorptions, independently from lesion size, and of lingual resorptions of 1.2 mm or greater. DSR was significantly better than DR for detection of lingual resorptions up to 1 mm. Resorptions less than 0.5 mm were not precisely detected by either method. DSR provided better intraexaminer and interexaminer agreement than did DR.
  
  
  CONCLUSIONS
  Both methods are precise for detection of apical root resorptions as small as 0.5 mm and lingual resorptions of 1 mm or more. However, DSR frequently performed better than did DR.
authors.affiliation: Department of Oral Diagnosis and Surgery, São José dos Campos Dental School, São Paulo State University, São José dos Campos, São Paulo, Brazil. evelise.ono@uol.com.br
authors.forename: Evelise
authors.initials: E
authors.lastname: Ono
authors.forename: Edmundo
authors.initials: E
authors.lastname: Medici Filho
authors.forename: Horacio
authors.initials: H
authors.lastname: Faig Leite
authors.forename: Jefferson Luis Oshiro
authors.initials: JL
authors.lastname: Tanaka
authors.forename: Mari Eli Leonelli
authors.initials: ME
authors.lastname: De Moraes
authors.forename: Julio Cezar
authors.initials: JC
authors.lastname: De Melo Castilho
mesh_terms: D019540:Area Under Curve; D001641:Bicuspid / Q000000981:diagnostic imaging; D003481:Cuspid / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000592:standards; D007180:Incisor / Q000000981:diagnostic imaging; D009811:Odontometry; D012372:ROC Curve; D019252:Radiography, Dental, Digital / Q000592:standards*; D012391:Root Resorption / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D013382:Subtraction Technique / Q000592:standards*; D019227:Tooth Apex / Q000000981:diagnostic imaging; D014092:Tooth Root / Q000000981:diagnostic imaging